How to Remove Optical Brightener from Cotton Fabric
Optical brightener is being added in the cotton fabric to give more brightness . It is visible in Ultra Violet Rays more . As these rays are presence in sunlight , hence bright white can be easily identified in Sun light . Some times it is not needed in the fabric. It comes as contamination due to processing mistakes. And in some product OBA is banned in some country or some branded garment also. So the removal of OBA is needed in such condition.
The simple way is to insure Machines are properly clean before running non oba fabric . But even though if it has come as contamination , Then it can be removed by HCl (Hydro chloric acid) .
When we use HCl it should be of 35% strength , And it should be use at temp 40 deg c , by dosage not more than 5 gpl.
After this treatment fabric has to be properly washed off.
and properly neutralized also .
As presence of HCl in fabric may tender fabric under heat .